/*
 * @Descripttion: 
 * @version: 
 * @Date: 2020-10-12 11:33:22
 * @LastEditTime: 2021-01-14 14:24:15
 */

const Cesium = require('cesium/Build/Cesium/Cesium')

/**
 *飞行轨迹对象
 *
 * @export
 * @class PolylineTrailMaterialProperty
 */
export class PolylineTrailMaterialProperty {

    /**
     * 
     * @param {*} options 参数
     */
    constructor(options) {
        options = Cesium.defaultValue(options, Cesium.defaultValue.EMPTY_OBJECT);
        this._definitionChanged = new Cesium.Event();
        this._color = undefined;
        this._colorSubscription = undefined;
        this.color = options.color;
        this.duration = options.duration;
        this.trailImage = options.trailImage;
        this._time = performance.now();
    }
}

Object.defineProperties(PolylineTrailMaterialProperty.prototype, {
    isConstant: {
        get: () => false,
    },
    definitionChanged: {
        // eslint-disable-next-line require-jsdoc
        get: function () { return this._definitionChanged },
    },
    color: Cesium.createPropertyDescriptor('color')
});

PolylineTrailMaterialProperty.prototype.getType = function (time) {
    return 'PolylineTrail';
}

PolylineTrailMaterialProperty.prototype.getValue = function (time, result) {
    if (!Cesium.defined(result)) {
        result = {};
    }
    result.color = Cesium.Property.getValueOrClonedDefault(this._color, time, Cesium.Color.WHITE, result.color);
    //result.image = Cesium.Material.PolylineTrailImage;
    result.image = this.trailImage;
    result.time = (performance.now() - this._time) % this.duration / this.duration;
    return result;
}

PolylineTrailMaterialProperty.prototype.equals = function (other) {
    return this === other || other instanceof PolylineTrailMaterialProperty &&
        Cesium.Property.equals(this._color, other._color)
}

Cesium.Material.PolylineTrailType = 'PolylineTrail';

Cesium.Material.PolylineTrailImage = "./assets/flyPolyline/colors1.png";

// eslint-disable-next-line no-multi-str
Cesium.Material.PolylineTrailSource = "czm_material czm_getMaterial(czm_materialInput materialInput)\n\
{\n\
    czm_material material = czm_getDefaultMaterial(materialInput); \n\
    vec2 st = materialInput.st; \n\
    vec4 colorImage = texture2D(image, vec2(fract(st.s - time), st.t)); \n\
    material.alpha = colorImage.a * color.a; \n\
    material.diffuse = (colorImage.rgb + color.rgb) / 2.0; \n\
    return material; \n\
}";

Cesium.Material._materialCache.addMaterial(Cesium.Material.PolylineTrailType, {
    fabric: {
        type: Cesium.Material.PolylineTrailType,
        uniforms: {
            color: new Cesium.Color(1.0, 0.0, 0.0, 0.5),
            image: Cesium.Material.PolylineTrailImage,
            time: 0
        },
        source: Cesium.Material.PolylineTrailSource
    },
    translucent: () => true,
});
